A High-Coverage Epitope-Based Vaccine Design for EIAV Envelope Polyprotein Using an Immunoinformatic Approach

Equine Infectious Anemia (EIA) is a retroviral disease of equids, for which there is no vaccine particularly adapted to American viral strains. In this work we searched for possible epitope regions for the surface proteins gp90 and gp45, rationally employing the latest available bioinformatics tools that constitute the state of the art in the field. We selected eight regions that contain numerous overlapping epitopes that have a high coverage amongst American viral strains and designed a chimeric envelope protein with those proteins fused in tandem as a novel vaccine candidate. In silico predictors were used to analyze chimeric protein physicochemical and immunogenic properties, as well as its allergenicity and toxicity. Protein structure was predicted and validated, and its ability to trigger cytotoxic immune responses was predicted by molecular docking to ELA alleles. The proposed sequence is predicted to be highly immunogenic and sets the base for a novel EIAV vaccine that could be used to protect against several American field strains.